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gregt
03/06/2003, 09:30 AM
Thanks for the effort of doing the assay. I'm sure the wife is very happy that it is done. ;)

I'm having trouble with your conclusion that heavy metals are responsible for the survival results in your assay.

The two salts that made artificial seawater with the lowest survivorship of larvae consistently have heavy metals concentrations hundreds to hundreds of thousands times those found in natural seawater.

Perhaps I'm missing something but let me explain my confusion.

If I understand correctly, your conclusion is based on the fact that there is a correlation of survival rates to heavy metal concentrations. This would seem obvious when comparing NSW and the artifical mixes. There is significantly larger amounts of heavy metals in the mixes and likewise a significantly lower survival rate in the assay. Based on that it is logical to suggest that heavy metals are a likely causative agent.

However, if you use the same criteria in comparing the two commercially available artificial mixes (IO and coralife), you come to the inverse conclusion. IO, in fact is lower in all metals except Manganese, Potassium, Sodium, and Strontium, of which none are the commonly "worried about" metals. Despite this, the survival rates of IO are roughly half that of Coralife, which is not what I would have expected if heavy metal concentrations are causative. I would have expected them to be similar or IO to have a worse survival rate.

This suggests to me that there is more at work here than simply heavy metals.

Do I find the levels of heavy metals in our salt mixes acceptible? Absolutely not, but based on my own personal experience with one of the commercial salts involved, I'm not quite ready to change my salt brand yet.

Any comments are appreciated,

rshimek
03/06/2003, 11:11 AM
Hi Greg,

There is no discernable difference between the survival rates in IO and Corallife (they are not statistically different), so regardless of the absolute survival, we have to consider them as being the same.

Both of these salts are effectively heavy metal cocktail mixes.

Strontium has been documented in the scientific literature to poison corals, but it is a weak poison, and probably doesn't kill them unless present in very high doses. The others you mentioned may have some effect but are not generally considered to be toxic.

Almost of the heavy metals have been demonstrated to kill either corals or other inverts at concentrations far lower than are found in the mixes.

This correlation indicates, to me, that the metals are the cause.

However, this is a correlative study, and perhaps some other factor is in play. After all, one can not use correlation to prove or disprove anything.

It would take extensive and expensive testing to pin down the specific chemical actors in this drama, but I suggest that the smoking gun certainly points to excessive heavy metal concentrations.

gregt
03/06/2003, 11:43 AM
I understand everything in your response and agree with almost all of it, especially this:

Both of these salts are effectively heavy metal cocktail mixes.

However, I don't understand how you determine that a survival rate differential of a factor of two to be "indiscernable".

I'm also not ready to reject my years of success with this particular salt as I've not had a death not attributed to a mistake in husbandry in over 4 years using this salt, so understandably, I'm not easily convinced that it's certain death, so to speak. ;)

WaterKeeper
03/06/2003, 12:50 PM
Greg,

I have been one of the advocates for water changes in various threads in this forum. Doc Shimeks latest bioassay results have thrown some doubts in my mind of the quality of IO, which is the salt I use. I, like you, have not seen any harmful effects in my tanks from using IO but there was pretty solid evidence in this latest article that IO has a negative effect on certain marine invertebrates.

The purple urchin is used in many studies and has a known susceptibility to low levels of toxicity. In that regard it is like Cerio Daphnia Dubia used in fresh water bioassays. I have heard laboratory people using this daphnia exclaim it dies if one utters a disparaging word :D . I would like to see some further evidence such as a bioassay using Mendia Beryllina, the inland silverside. They are more tolerant of heavy metals than Arbacia.

Overall however, I found this latest article very revealing and hope the manufacturers of artificial salt mixes will take heed. Even if it's not a problem with "heavy" metals it appears that something in the IO and Corallife mixes had an adverse effect in this study.

rshimek
03/06/2003, 07:13 PM
Originally posted by gregt

Hi,

However, I don't understand how you determine that a survival rate differential of a factor of two to be "indiscernable".

The means differ by a factor of two, but the variances are large enough to overlap, indicating that the two sample means are not statistically distinguishable. Basically, they sample averages are not sufficiently different enough to distinguish through the background noise.

I'm also not ready to reject my years of success with this particular salt as I've not had a death not attributed to a mistake in husbandry in over 4 years using this salt, so understandably, I'm not easily convinced that it's certain death, so to speak.

Whatever. :D

Unless something is detoxifying them, the metals loadings in the salts are sufficient to cause problems with every animal immersed in them. You speak of success, but without a control you really can't tell if these salts are allowing "success" or simply "existence." My guess is that for some species, there are tolerances to heavy metals, for others less so. The former would do all right for a while in these soups, the latter wouldn't. There are very great number of animals that don't survive in our present salt mixes, and I suspect the major reason is heavy metal intolerances. Additionally, we have almost zero success at sexually reproducing animals in our systems, and this is almost certainly due to the metal toxicity. Finally, even among the corals, for example, that we can keep, many clones simply don't thrive.

gregt
03/06/2003, 07:23 PM
You may say "whatever" to my success, or perhaps lack of failure is a better way of saying it, but as I said, I've yet to lose any species I've tried (and the list is quite long), due to anything other than stupid mistakes in husbandry. Also, I've experienced excellent growth of most species with a few exceptions.

As for the breeding, I can't argue there, but that's a problem I don't want in my display tanks, as it would cause many more problems than it would solve.

That said, I thought I'd made it quite clear I do have a problem with the levels of heavy metals in the mixes in principle. I'm just not convinced based on my experience that it's anything to boycott specific brands on just yet.

rshimek
03/06/2003, 07:46 PM
Hi Greg,

Well, you might consider that if the levels of the metals seen in these salts were measured in nature, the area would be considered to exceptionally highly polluted; enough so that it would likely qualify as a superfund site here in the states.

The Bioassay formulation has been used by folks for years in the aquaculture industry - it was initially marketed to them because of the mortality they were getting with the standard aquarium salts, so it is a tried and true product.

I obviously am not going to convince you to change your salt mix, but speaking as invertebrate zoologist, it would be far better for your animals to be either in natural sea water or in the closest possible analogue to it rather than in a material that causes such high larval mortality.

jacmyoung
03/06/2003, 07:54 PM
I too have some problem with how the bioassays were presented and the way the conclusions were made.

Dr. Ron had in the past conducted many scientific studies and I tended to side with his discoveries more so than some other skeptics. But what puzzled me this time is why only four commercially available salts were used, and why the results of the two samples provided by the hobbyists were brushed off some what.

The toxicity studies on the number of the tank samples Dr. Ron did before were limited mainly because of the lab costs involved, but this bioassay study was not very limited by the cost per test. One would have easily obtained many more salt mixes (and there are many many more of them on the market) to be included in the study.

In addition, the freshly mixed salt water did not represent a typical water condition from a typical reef tank. Therefore I thought more weight should have been given to the results of the two tank samples and wished more tank samples of different salt mixes would have been used in the study.

While I don't dispute the notion that high levels of metals are bad for reef inhabitants, making a conclusion that the two brands of salts are superior to the two other brands of salts after this initial round of biosassays seemed premature or at least lacked scientific discipline.

While I certainly am not making any bid of accusation or implication, reading the above article was like reading a study conducted by a manufacture published in a newpaper ad, certainly not typical of Dr. Ron's work that I am familiar with.

gregt
03/06/2003, 08:01 PM
Well, you might consider that if the levels of the metals seen in these salts were measured in nature, the area would be considered to exceptionally highly polluted; enough so that it would likely qualify as a superfund site here in the states.

True, but you can apply the same statement to the levels of bacteria and organics in our tanks, only more so.

I obviously am not going to convince you to change your salt mix

Not based on this assay alone, no. Because I have to go with what I see rather than what an assay tells me. If you did a test that concluded that I'm a tall, thin, handsome, clever person, that attracts beautiful women in droves, I may be pleased, but it's not going to change reality. ;) In this case, the reality is I'm not seeing any evidence of mortality or poor health due to my choice of salt mix so the test isn't going to change my mind. That doesn't mean that I don't want salt that has has less heavy metals, it simply means I'm not going to react without more information.

Again, I don't think this is a non issue, I do think that it is less of an issue than ammonia, nitrate, shipping, cyanide, nutrition, acclimation, chemical warfare, general levels of organics, soap on your hands, etc, etc, etc . . .

Skipper
03/06/2003, 08:10 PM
jacmyoung:

In another thread in this forum Dr. Ron responded:
The bottom line on what was tested and what wasn't....

1)I used IO and it is the most popular salt, so I wanted to test it.

2)There have been some questions about Coralife for years, so I wanted to test it.

3)Dennis Tagrin of DT's said that the salt he used in his culturing was low in heavy metals, so I wanted to test it.

4)A hobbyist who heard I was running the tests sent me a free bag of the Bio-Sea, so I tested it.

At this point, I had enough physical space in my office lab for the 88 beakers that testing 4 salts, 2 hobbyists, 2 controls would entail.

And, at this point, I had spent about $1000 in equipment, supplies, urchins, and chemicals for the test.

So I went with that.

Another experimental run would cost about another $500 to $750. I could not and can not afford to do another one, so I didn't test any of the other salts.

That should clear up any confusion you have.

jacmyoung
03/06/2003, 08:40 PM
Originally posted by Skipper
jacmyoung:

In another thread in this forum Dr. Ron responded:

That should clear up any confusion you have.

While some of my questions were answered, others did not change. It however raised some new questions. For example the reason why some of the salts were selected in the study seem to indicate a less than impartial position going into the study.

If IO was chosen due to its popularity, the conclusion Dr. Ron made after his bioassays would appear more "grand" than usual, and a grand conslusion requires an equally grand discovery, not just a simple test.

Did anyone bother to ask then why IO was so popular? I am sure with over 60% of reefers using IO (from one of the non-scientific polls taken on another forum), someone must have noticed something bad about IO compared to other salts?

I am not trying to dispute the bioassays Dr. Ron has conducted and the analyses afterwards, only that the study at best calls for more similar studies, not the end of a debate which salt is superior which is not.

jacmyoung
03/06/2003, 09:30 PM
Let me just add that as critical as I might have sound, I am grateful for Dr. Ron's work in the past and the present. If enough people switch their salt mixes, may be we will get some representive reports from the reefers to support Dr. Ron's theory, or if not we may found something else worth noting as the result of this study.

Martyn
03/07/2003, 12:36 AM
Hi Ron
An interesting survey something for me to think about.

gregt

just a couple of questions for you.
In Sept 2000 you set up a new tank prior to that you had a tank running for 6 years.

On the 10th of sept you said.
I can't use anything thats ever touched my display tank, as this tanks purpose is to isolate new fish from the display tank until it has proved healthy.
Then I will add it to the tank to see how it does.
I'm trying to prove conclusively that there is something in my display that is killing my fish.

So is the tank you now have the 2 years and 5 months old tank the reef tank and what was killing your fish in the FOWLR at that time?

I am interested as you point out you have been using the salt you use for 4 years with no problems and you say your lack of failure is a better way of saying it, but as I said, I've yet to lose any species.
But you set up a new tank in sept 2000 and you had something killing your fish around that time.

Also I presume the tank you had running for 6 years prior to the new tank at that time was a 55 Gallon FOWLR and the new tank was the reef tank?

And in Feb 2001 you added corals to the FOWLR.
And you have only had a reef tank for 2 years and 5 months from cycling this tank with live rock.
Or am I missing something?
Please correct me if I am wrong.

Regards
Martyn

gregt
03/07/2003, 06:26 AM
Hi Martyn,

Let me clarify a few things. When I said "species" I was referring to corals, not fish. You are correct in that I did have some trouble keeping newly added fish alive in that tank particular tank, however species commonly known to be highly intolerant to heavy metals were not having problems (such as snails, crabs, etc), so that is not relevant, IMO. Additionally, everything in the tank was moved to the new tank which exception of the substrate.

Sadly, I never was able to explain the fish deaths, however, they stopped after an extended period of the tank having no fish, and I never changed salt mixes. This indicates to me that it was some type of communical disease or paracite. It certainly doesn't seem at all likely it could have been related to heavy metal poisioning.

Dr. Ron, what is your opinion on that matter?

Randy Holmes-Farley
03/07/2003, 10:02 AM
Greg:


I'm having trouble with your conclusion that heavy metals are responsible for the survival results in your assay.

I think that the metals explanation of the significant differences obtained is a good hypothesis. But there are potentially many other differences between the samples that could also be the "true" explanation. Ammonia, pH, nitrite, nitrate, sulfate, organics, and a host of other chemical atttributes remain possibilities.

rshimek
03/07/2003, 12:33 PM
Hi Randy,

So... set up and run the tests. :D

At the present time, as I indicated earlier, we don't know what is causing the differences. Heavy metals concentrations as high as are found in the mixes are considered to be problems in marine systems whereever they are found. I think that they are most reasonable potential cause of the results I obtained, but there certainly could be other causes.

The field is open for other folks to do some controlled tests. I welcome any additional results.

:D

rshimek
03/07/2003, 12:40 PM
Originally posted by gregt

Hi Greg,

. It certainly doesn't seem at all likely it could have been related to heavy metal poisioning.

Actually, it might be. Randy and Habib have postulated that heavy metal toxicity in tanks is reduced by bacterially generated materials or other materials such as humic acids. Once a tank is set up for any length of time, it is effectively a bacterial culture vessel and these organisms cover every surface in it. That some tanks can start with a salt that kills larva and still support life well, is evidenced by the one hobbyist in the study whose water did pretty well. The "freshly mixed" salt water would be "nasty," the older water would be less so, and may well be below the level of acute problems.

palkin-kopalkin
03/07/2003, 12:45 PM
This is for Greg,
Maybe I missed it but what type of salt do you use?

gregt
03/07/2003, 12:55 PM
Dr. Ron,

Did you see that the problem was with newly added fish? They were dying in a one to two week period of adding them to the tank. After leaving the tank empty for three months (I honestly don't remember whether water changes were done during or immediately after that period. I probably have logs with that information somewhere . . .). New fish added after the three month period were fine.

Also, if it was heavy metal poisioning, wouldn't the snails, crabs and other inverts die long before fish?

palkin-kopalkin, I didn't say.

barry769
03/07/2003, 12:58 PM
Originally posted by rshimek

Actually, it might be. Randy and Habib have postulated that heavy metal toxicity in tanks is reduced by bacterially generated materials or other materials such as humic acids. Once a tank is set up for any length of time, it is effectively a bacterial culture vessel and these organisms cover every surface in it. That some tanks can start with a salt that kills larva and still support life well, is evidenced by the one hobbyist in the study whose water did pretty well. The "freshly mixed" salt water would be "nasty," the older water would be less so, and may well be below the level of acute problems.

I am wondering if this might be related at all to the reason why many of the less hardy additions to our tank, such as corals anemones and some fish, must wait 6 months before the tank "matures", long after the initial cycling of the tank has finished.

-Scott

rshimek
03/07/2003, 02:45 PM
Hi Greg,

Did you see that the problem was with newly added fish? They were dying in a one to two week period of adding them to the tank.

Such a mortality pattern would be consistent with fish dying of acute poisioning. - As well as, of course, some other things. Simply can't tell by this distance.

New fish added after the three month period were fine.

If some factor in the tank was reducing the mortality to toxic effects, waiting would work in your favor.

Also, if it was heavy metal poisioning, wouldn't the snails, crabs and other inverts die long before fish?

Not necessarily. A lot of survival to this stuff depends on acclimation, and if they were already acclimated to it, they could be surviving by detoxifying the metals loads. I think a lot of "salinity" acclimation problems have nothing to do with salinity, but everything to do with metals detoxification.

It is hard to make generalities about toxicity across different animal groups, some snails and such are quite prone to dying in any elevated metal environment, but there are a few which are quite hardy.

Scott,

You said, "I am wondering if this might be related at all to the reason why many of the less hardy additions to our tank, such as corals anemones and some fish, must wait 6 months before the tank "matures", long after the initial cycling of the tank has finished."

Yes, I think that is precisely why that that happens.

Dietsip
03/07/2003, 05:41 PM
Originally posted by Randy Holmes-Farley

I think that the metals explanation of the significant differences obtained is a good hypothesis. But there are potentially many other differences between the samples that could also be the "true" explanation. Ammonia, pH, nitrite, nitrate, sulfate, organics, and a host of other chemical atttributes remain possibilities. [/B]

But the fact remains that the salts used as directed in the concentrations the manufacture provides gave the results Dr. Ron obtained.

Bomber
03/07/2003, 06:09 PM
Such a mortality pattern would be consistent with fish dying of acute poisioning. - As well as, of course, some other things.

Strange, on the surface it would seem that way. However, allowing for "acclimation" and "resistance", there should be some survivors. This is actually more indicative of a disease problem, rather than a environmental problem.

Also, if it was heavy metal poisioning, wouldn't the snails, crabs and other inverts die long before fish?

Yes

rshimek
03/07/2003, 06:39 PM
Actually quite a number of common mollusks, worms, and other invertebrates are tolerant of heavy metal pollution, so much so that they are referred to as "pollution indicators." Along the Pacific coast, these include species amphipod genera (particularly gammarids) and some species of trochid snails, and several species of common anemones.

I am unfamiliar with any tests done with any of the common marine aquarium animals that show any quantitative data of metals tolerance, other than the ones cited in the study. We have plenty of anecdotal information however, that indicates at least most species commonly kept are somewhat tolerant (after all they exist in IO water....).

ausnakeguy1
03/07/2003, 07:12 PM
Did anyone bother to ask then why IO was so popular? I am sure with over 60% of reefers using IO (from one of the non-scientific polls taken on another forum), someone must have noticed something bad about IO compared to other salts?

Actually it has to do with marketing believe it or not. The picture of the Clown Fish in its host anemone with such pretty tips, and colors is a highly attributable factor in the choice of IO over other brands. We actually looked at this in my Strategic promotions course, the professor is into Reefs and he always wondered why one salt sold better than the other when they were basically all the same. One of the things that came up in the study was that the Clown fish is a big symbol of the Salt Water tank, and of keeping tanks. Ask any non reefer or even reefer why they joined the hobby, and whats a salt water fish you want to have and most will say it was so they could have a cute little clown fish. By IO putting that clown fish on the bucket and packaging it caused a Hedonic response as we call it in marketing, causeing the consumer to use emotions to do the purchasing. They think well if i buy this product then i can have my clown fish and all the pretty colors.

While you may say no you don't, actually you do unless you did the tests for it to see which one was closest to Sea Water. When you look at a bucket of Kent with the red label, and a bucket of Red Sea with its little pristine pictures and a pic of IO with the HUGE clownfish on it. The Clownfish causes an emotion response and then causes various other responses most of which you aren't even aware you are doing.

Also, if it was heavy metal poisioning, wouldn't the snails, crabs and other inverts die long before fish?

No Boomer they wouldn't, in LongIsland were my family has lived for over 80 years now, we have a salt creek in the back. And in this creek are many mussels and Long neck clams. You can NOT eat these animals unless you want to get very sick from the increadibly high concentrations of Arsenic and Mercury found in these creatures. So no they wont' necissarily die first. As Dr. Ron said they are an indicator of the health of the area, i also believe that corals will incorporate these various metals into their skelletons. Is this true Dr. Ron?

And thanks for taking time out of your life and putting your money towards doint this study. A lot of us appreciate it.

Bomber
03/07/2003, 07:18 PM
I sorry there's a little confusion here. Greg had astreas in his tank, not long necks.

ausnakeguy1
03/07/2003, 07:30 PM
ha ha...funny guy you are bomer. You know what I am saying.

gregt
03/07/2003, 07:31 PM
I don't know what you or Ron are saying on this. We aren't talking about theoretical species that may be tolerant, we're talking about astreas which are not.

ausnakeguy1
03/07/2003, 07:38 PM
Greg,
I am not talking about theoretical speices, a Long neck clam is a real speices I don't know the genus or spieces but they are a real creature, I know I've played with them, dug them up out of the sand, etc when I was a little kid.

And I put that foward with Boomers post of if the Metals were built up in the tank to toxic levles that the inverts would die before the fish. While Astreas, turbos, etc may be very sensitive to toxic metals, I was simply showing a flaw in Boomers statement he'd said woudln't the snails, crabs and other inverts die before the fish. That encompases more than just Astreas. Thats why I put that up there to show that no not all inverts are as sensitive to heavy metals and therefore you woudln't see a problem.

parakeet
03/07/2003, 07:53 PM
Couldn't the right balance of elements be economically harvested from the sea itself(in clean locations)? It must be feasible, because I have seen sea salt for sale at the supermarket. Correct me if I'm wrong.

gregt
03/07/2003, 08:05 PM
They are theoretical, because they weren't in my tank. Astreas were in my tank. To assert that it's possible for my fish to die when my astreas didn't because long neck clams and some mussels are tolerant makes no sense whatsoever.

The point is, lets stick to the subject of how the animals actually in my tank that are not known to be tolerant somehow managed to live when fish, which typically are much more tolerant died quickly.

ausnakeguy1
03/07/2003, 08:08 PM
Parakeet, I asked that question in another forum and I think it was Randy who told me that when you dehydrate the sea water there are certain elements that will not go back into solution, what thoes elements and compounds are i could not tell you.

traveller7
03/07/2003, 08:51 PM
Originally posted by gregt
The point is, lets stick to the subject of how the animals actually in my tank that are not known to be tolerant somehow managed to live when fish, which typically are much more tolerant died quickly.

Hate to say it, but everything going forward on the past deaths will likely exist as unproven theory. It may be possible to rule out factors (metals) by testing substrate, live snail shells, etc.

Best of luck and may there be no repeat under your care.

parakeet
03/07/2003, 08:54 PM
Thanks, that makes sense.

MamaJude
03/08/2003, 02:31 AM
Dr. Ron...

I have a question...I have been a hobbyist for over 30 years, 25 or so which have been solely marine. I have used Instant Ocean and Kent Marine pretty much exclusively. I had a mated pair of percula clowns that spawned all the time. I do believe that the results of your testing are exactly what you have published, but in all honesty, can you say definitively that it was toxic metals that killed the urchin larvae and were causing the problem in your tank?

It would seem to me that in order to substantiate your results, the true cause of the death of the dead urchins should have been established beyond a doubt. And if you say that over time, these metals will contaminate a long lived tank, then where are the tests taken on mature tanks to substantiate this fact?
While I agree that your results seem to point in that direction, I have not read anything that actually shows proof of that to be true. And if it is not true, then what happened to the accumulation that you say is likely? If a mature tank is likely to export these metals, however it is done (and I am no marine biologist) then it seems to me that a tank should be set up, matured and then the critters added, and this debate on salt mixes is irrelevant.

Also, in another thread, the salt poll, dendronepthya states that as an undergraduate, in the biology class that was taken, they raised the same exact urchin you did in Instant Ocean and had no significant mortally such as you experienced. Don't you find this a bit puzzling?

Please know that I am not putting down your testing, nor denegrating its results, only noting that I find your conclusions a bit premature. If the study was meant to provoke thought and query into the composition of salt mixes, then it has done its work. I, for one, would be glad to contribute to an independantly done study on the long term effects of the different salt mixes. As a hobbyist very immersed in the hobby, I would certainly like to do what is best for my reef tank.

With all due respect,
Jude

MamaJude
03/08/2003, 04:00 AM
Dr. Ron...

Sorry. I was reading some of your other threads on the salt issue after I posted my original query. Is the supposition that you had your rock and sand tested for heavy metals true? If so, what were your findings? Also, it seems that you say that the release of heavy metals from the sand bed and/or rock comes at lower ph? If your tank was declining slowly, wouldn't it be an accurate supposition to assume that your water would be holding the metal too, since you assume that toxic metal was the culprit in your own case of OTS?

If the sand and rock were saturated, then the metal would be discernable in the water, correct? At least I think that was what you were meaning. So, following that logic, then the metal would be removable by the filter pads, or other methods, perhaps skimming. I used to use a product a long time ago manufactured by Hawaiian Marine that was called Hydrokoll. It was supposed to bind with heavy metals and remove them from the tank via your skimmer. Have you ever heard of this?

Very interesting threads we have here. I hope that you don't take my questions as a stab at your dedication or your motives. I respect anyone who takes the initiative to find out what may be the culprit when something happens to a stable environment. I did the same thing when my cat died of FIP.

As my vet once told me, while it is true that veterinarians and other learned colleagues advance the quality of life for animals, it is often the pet owner, who in search of answers to unanswered questions, stumbles on a direction that leads to the ultimate answer. I would hope that the same applies to all of the hobbyists here. As we try different things to make life richer for our reefs, we also may aid in finding the "right" answer to all of our unanswered questions. Since you have a vast following here, the answer to a lot of our questions may lie in the sharing of information in regards to this hobby.

Thanks for caring

Jude

rshimek
03/08/2003, 07:46 AM
Originally posted by MamaJude

Hi,

I do believe that the results of your testing are exactly what you have published, but in all honesty, can you say definitively that it was toxic metals that killed the urchin larvae and were causing the problem in your tank?

No, I test survivability of the urchin larvae, and did not attempt to determine the cause. The excessively high heavy metals concentrations in the salts with the highest mortality prompted me to propose the hypothesis that the metals caused the mortality.

It would seem to me that in order to substantiate your results, the true cause of the death of the dead urchins should have been established beyond a doubt.

No. The urchins did not do as well in 2 of the salts tested. Those are the results. I didn't attempt to determine the cause of death.

And if you say that over time, these metals will contaminate a long lived tank, then where are the tests taken on mature tanks to substantiate this fact?

Scan through my articles over the last year in <b><a href="http://reefkeeping.com" target="_blank">Reefkeeping Magazine</a></b>


Also, in another thread, the salt poll, dendronepthya states that as an undergraduate, in the biology class that was taken, they raised the same exact urchin you did in Instant Ocean and had no significant mortally such as you experienced. Don't you find this a bit puzzling?

No, I have had student raise urchins in it my classes as well. However, generally the survivability in these classes is quite low. But in a class situation that doesn't matter. All you want is to have some survive.

I, for one, would be glad to contribute to an independantly done study on the long term effects of the different salt mixes.

And, gee, just how is my study not an independent on? I am not employed, paid or reimbursed by any aquarium product manufacturer, and I have run bioassay facilities in the past.

If the sand and rock were saturated, then the metal would be discernable in the water, correct? At least I think that was what you were meaning. So, following that logic, then the metal would be removable by the filter pads, or other methods, perhaps skimming

Read the articles in <b><a href="http://reefkeeping.com" target="_blank">Reefkeeping Magazine</a></b>, start with a year ago February and work forward. You will find answers to most of your questions.

rshimek
03/08/2003, 07:51 AM
Originally posted by gregt

Hi Greg,

The point is, lets stick to the subject of how the animals actually in my tank that are not known to be tolerant somehow managed to live when fish, which typically are much more tolerant died quickly.

Actually, the point is that neither you, I, or anyone else knows why your fish died. :mixed: We can jaw about all we want, but we'll never come up a definitive answer and it is really hard to go back in time to get the appropriate evidence.

Frankly, I suspect in the case of your fish, it probably was disease that did 'em in. But, we don't know - and never will.

:D

MamaJude
03/08/2003, 03:26 PM
Dr. Ron...

I am a bit puzzled by the tone of your reply to me. As a hobbyist, and a concerned reefer, I was just asking questions about your findings and relaying to you some other data that might impact your conclusions in your study. I was in no way attacking your credibility or your sincerity about your work. You published your findings publicly; didn't you think you would have questions, especially considering that your following consists mainly of non phd people?

We are all trying to understand what you wrote, how you did things and what, if anything might have influenced your results. Questions are just that, although after reading the forums here, I can understand why someone would show a bit of hostility at the way some questions and comments were phrased.

You said that you hypothisized the conclusion. I can respect that. And if you had read the post following my first, you can see that I did do followup on your forums. It is a daunting task here to search through all the threads to find the answer, if you even do, to a question you might have. I thought the purpose of having you in this one was so that we might ask these questions and receive answers.

However, I must remind you that you are in a much different position than I am. Your specialty is definitely not mine. You are regarded as a definitive expert in your field. What you say can and will impact what people do here. As such you have a much greater responsibility because of your expertise to make sure that what you say is interpreted in the manner by which you meant it to be interpreted.

Quote:

"And, gee, just how is my study not an independent on? I am not employed, paid or reimbursed by any aquarium product manufacturer, and I have run bioassay facilities in the past."
***************************************************

And by the way, I did not mean to convey criticism of your study. I merely meant that I would be glad to contribute to another, longer term study to do further research into this matter. That is what research is, isn't it? At least, as far as I am aware, one study is not the definitive word on any subject matter. It merely points out a probable suspect and points to a probable culprit. The ensuing studies either cohoberates the original study or refutes it. And then the researches go on.

What is the prime goal of such research anyway? I would think it is to find the correct answer. You may very well be right on your conclusions. But I would think you would welcome further study into the matter, even if your conclusions turn out to be wrong. It should not be a matter of pride, or solicit anamosity, from you because I asked such questions, even if to you, they are very infantile.

Regards,
Jude

Skipper
03/08/2003, 03:33 PM
Hey Jude. FWIW... I didn't interpret anything Ron said as antagonistic to you.

Desert Fox
03/08/2003, 04:09 PM
Boy, i sure did. :rolleyes:

Blue skies,
~Fox~

Martyn
03/08/2003, 04:53 PM
Interpreting posts on bulleting boards when not face to face with the people you are discussing subjects with can take time to adjust to, it is so easy to miss Interpret replys and questions and also very easy to read into things written that are not there or ment.
The way things are worded can mean a number of ways to Interpret them I feel it can take time to adjust to writing and reading on BBs it can take time to know the style of the posters and to Interpret what is being said.
Also the more you have to keep explaining things often you do not always take time to read what is being said fully and often do not word things in reply as you ment them to sound and this can lead to miss understandings.
It can be so easy to upset people that do not understand what you are trying to say in questions and in replys miss Interpreting what is ment is common even when face to face often people are not on the same wave lengths.

Not sure if I am making any sence :D

Regards
Martyn

WaterKeeper
03/10/2003, 12:49 PM
Gentlemen-Gentlemen,

Please do not lose your objectivity here. What Ron did was run a very limited bioassay on a single species. The hypothesis was, "Is there a difference in the survival rate of larval Arbacia punctulata between four artificial seawater mixes and natural seawater?" His results indicated there were and, that two artificial seawater mixes had markedly statistical lower survival rates than the other mixes used in this study when compared to NSW. His conclusion was therefore that there might be toxicity factors present in some of the mixes that would raise questions in the mind of the aquarist about their suitability for use in their tanks.

The message was just a warning about this possibility;
NOT a wholesale condemnation of these products. It is unreasonable for anyone to draw conclusions that Ron had some sinister motive in publishing his results. Please, if you feel the results are in someway biased, attack the methodology or the conclusions drawn, not the man.

Eileen Herring
09/19/2003, 06:28 PM
In looking for info on the effects of aluminum in marine water on fin fishes, I have stumbled on your article which this forum discusses. I note that the two "really bad" mixes, IO and Coralife, have astronomical levels of Al as well as other metals. Mightn't Al be a likely culprit?
We have a situation here near Bellingham involving a catastrophically plummeting herring population and an aluminum smelter. Numerous studies have looked at the effects of petrochemicals on the fish (there are two refineries, as well), but no smoking gun has surfaced. Auminum studies are harder to find. Interestingly, one of the petrochemical studies I saw looked at egg hatch survival and morbidity in situ, against a control group hatched in local stream water to which IO was added. To the surprise of the investigators, the IO control group had more than twice the mortality of the eggs hatched in situ in polluted marine water. Your study certainly gives a possible explanation for this result, but in the case of our water here, Al is much more likely to be present than other metals. There was in fact a recent incident where Intalco was caught red-handed spilling alumina onto the water while unloading a barge.
So I'm somewhat avid to find studies of Al on fish survival, with the hope of lighting a fire under the Dept. of Ecology. If my ulterior motive violates the spirit of this forum, please accept my apology. Still, I'd be grateful to know of any such studies you may be aware of. It was a pleasant surprise to see the name of my old UAA professor referenced in an article which came my way.
Sincerely, Eileen Herring

gregt
09/19/2003, 09:25 PM
Eileen,
I took the liberty of posting your question in the Chemistry forum where there are a few people that have been looking at the effect of Al in reef tanks. They may be able to help you out.... Here's the thread:

http://archive.reefcentral.com/forums/showthread.php?s=&threadid=244188

Eileen Herring
09/19/2003, 10:36 PM
Greg,
Thank you very much.
Eileen

rshimek
09/20/2003, 08:09 AM
Originally posted by Eileen Herring

Hi Eileen,

[welcome]

In looking for info on the effects of aluminum in marine water on fin fishes, I have stumbled on your article which this forum discusses. I note that the two "really bad" mixes, IO and Coralife, have astronomical levels of Al as well as other metals. Mightn't Al be a likely culprit?

Yes, it surely might be. I haven't specifically looked at the effects of aluminum on inverts primarily because there are so few published data. Relatively lotsa data on some other metals, such as arsenic, copper, mercury, etc.

As you know, research into the effect of such materials is driven by human health concerns, and it is hard to find work on metals that are not directly implicated in human problems (either directly physiologically, or economically). Aluminum isn't of as much concern in this area as are the real nasty heavy metals, so it hasn't been looked at a lot.

I spent a fair bit of time in the Allen and Fish/Ocean Libraries at the UW campus about a year ago trying to track down the effects of metals on coral reef inverts (the thrust of my concern at the time) and while there is a lot on heavy metals, there is not a lot of work on some of the others.

... So I'm somewhat avid to find studies of Al on fish survival, with the hope of lighting a fire under the Dept. of Ecology.

Good luck. I spent a lot of time both working across the table from Wash DOE and Region X EPA (I was working for a firm called Parametrix, Inc., at the time - and the projects were ones such as the Asarco Arsenic Smelter in Tacoma, the Everett Carrier Homeport, and several others). Presently, I work as a contract taxonomist now and then for DOE.

Keep in mind this agency is underfunded and understaffed and with really limited expertise. Unless they hire some good people you may have some real problems getting them to respond.

Scanning through my data base I came up with the following articles that contain information about aluminum. I don't know if any of them will be of any help for you.

Scott,PJB; Davies,M (1997): Retroactive determination of industrial contaminants in tropical marine communities. Marine Pollution Bulletin 34, 975-980.
[ALUMINUM; ANTHOZOA; BIOINDICATOR; CADMIUM; CHROMIUM; CNIDARIA; COPPER; CORAL; LEAD; NICKEL; POLLUTION; TIN; TRACE METALS; VANADIUM; ZINC]

Morrison,RJ; Narayan,SP; Gangalya,P (2001): Trace element studies in Laucala Bay, Suva, Fiji. Marine Pollution Bulletin 42, 397-404.
[ALUMINUM; CADMIUM; COPPER; FIJI; IRON; LEAD; MERCURY; POLLUTION; SEDIMENTS; TRACE METALS; ZINC]

Booij,K; Hillebrand,MTJ; Nolting,RF; van Ooijen,J (2001): Nutrients, Trace Metals, and Organic Contaminants in Banten Bay, Indonesia. Marine Pollution Bulletin 42, 1187-1190.
[ALUMINUM; BANTEN BAY; CADMIUM; CHROMIUM; CONTAMINATION; COPPER; INDONESIA; IRON; LEAD; NICKEL; NUTRIENT LOADING; ORGANIC CONTAMINATION; SEDIMENTS; TRACE METALS; ZINC]

Very good to hear from you again after all these years.

Please feel free to contact me directly (rshimek@imt.net) if you think I might be able to help you further.

Eileen Herring
09/20/2003, 08:32 PM
Ron,
Many thanks for the articles, which I'm sure will be helpful. I'll send an e-mail soon; it's good to hear from you, too.
Regards, Eileen